Radio frequency communications such as cellular, WiFi, Bluetooth, Zigbee, etc. require a range of different frequencies and circuit filtering techniques to facilitate clear communication. RF antennas are increasingly required to operate over wider ranges of frequencies, resulting in performance degradation across frequencies. Current techniques to tune antennas involve switching banks of discrete capacitors that involve feedback and complex algorithms. Lumped matching networks provide discrete frequency filtering but suffer from significant insertion loss and are difficult to tune in real time. Current techniques also consume significant power and do not provide fine tuning to achieve high Q. It would be extremely beneficial to provide passively self-tuning impedance matching circuits to improve power and signal transfer, reduce wasted power consumption and signal reflection, and reduce algorithm complexity needed to tune discrete networks. In addition, energy harvesting and inductively coupled power transfer circuits are sensitive to impedance matching but do not employ economically viable methods to self-tune impedance to maximize power transfer.
This “Discussion of the Background” section is provided for background information only. The statements in this “Discussion of the Background” are not an admission that the subject matter disclosed in this “Discussion of the Background” section constitutes prior art to the present disclosure, and no part of this “Discussion of the Background” section may be used as an admission that any part of this application, including this “Discussion of the Background” section, constitutes prior art to the present disclosure.